Hepatic cirrhosis is a chronic illness of the liver, where diffuse cell necrosis and a limited regeneration of parenchymal hepatic cells result in diffuse percentage increase of connective tissue, causing the distortion of lobular hepatic architecture and inducing hemodynamic alterations. Therefore, some strategies for the treatment of hepatic cirrhosis could include the prevention and/or reversion of the fibrogenesis, stimulation of hepatic mitosis and re-arrangement of the architecture of hepatic tissue. The documents of the state of the art related to the present invention are mentioned hereinafter only as references.
U.S. Pat. No. 5,240,846 relates to the use of gene therapy called “CFTR”, which induces a stable correction of the regulation of the chlorine channel. This defect is present in epithelial cells. In said invention, adenoviral recombinant vectors are used as well as plasmidic vectors. However, it does not have any association with the therapeutics genes of the present invention. Likewise, U.S. Pat. No. 5,910,487 describes the use of plasmidic vectors for sending therapeutic molecules, but there is no association with the delivery of wild and/or modified huPA genes or of the TGF-beta (Transforming Growth Factor-beta) Type II truncated receptor genes as presented here. U.S. Pat. No. 5,827,703 refers to the use of adenoviral vector and modified adenoviral vector to send genes, however, none of these vectors contain the genes used in the present invention for the treatment of fibrosis.
U.S. Pat. No. 5,770,442 claims the use of a recombinant adenovirus that contains one gene directing the expression of a protein called “fiber” or a protein called “fiber-chimera”, however said patent does not specifically mention, which one is the therapeutic gene. Moreover, a method of gene therapy involving the use of such adenovirus and a vector of transference for the generation of such recombinant adenovirus is presented. However, nothing is mentioned with regard to the use of therapeutic genes cloned arid inserted in recombinant adenoviral vectors used in this invention in fibrotic livers, or to other target organs such as kidney, lung, and hypertrophic scars and others. These therapeutic genes are the gene that codes for the wild and/or modified huPA activator and the TGF-beta (Transforming Growth Factor-beta) type II truncated receptor, claimed in the instant invention. Other members of the family of genes represented are also included.
U.S. Pat. No. 5,166,320 refers to the use of a targeted delivery system to introduce exogenous genes in mammalian hepatic cells. But there is no association with putative genes directly sent to fibrotic livers, kidneys, lungs or other fibrotic organs.
U.S. Pat. No. 5,872,154 describes a method to reduce the immune response induced by an adenoviral recombinant vector through co-administration of recombinant adenoviral vector and a selected immune modulator, which functions by inhibiting the formation of neutralizing antibodies and/or reducing the death of the virally infected cells. U.S. Pat. No. 5,871,982 is directed to a hybrid vector, in which a portion of an adenovirus is included, together with a portion of an adeno-associated viral vector that contains a selected transgene. A hybrid virus consisting of the union of a conjugate with a polycation to a gene mesh of the adeno-associated viral vector to form a simple particle is also described. This is contrary to the present invention in which no hybrid viruses are employed, only adenoviral vectors. Besides, in the above-mentioned patent the gene, transgene or therapeutic gene used is not stated. U.S. Pat. No. 5,856,152 is directed to the creation of a hybrid vector that contains the portion of an adenoviral vector in combination with an adeno-associated virus and a selected gene, through which large quantities of recombinant vectors are produced, but they are not carrying cloned therapeutic genes as described in this invention, in which specific therapeutic genes for the treatment of liver, kidney, pancreas, heart fibrosis as well as keloids and hypertrophic scars are used. U.S. Pat. No. 5,547,932 claims a compound of nucleic acid complexes for transfecting eucaryotic cells. These complexes are formed by nucleic acids and another substance with affinity for nucleic acids and optionally an internalizing factor, such as a virus or a component of the virus that can be conjugated. It also uses components of specific adenoviral vectors or specific viruses such as Ad2 or Ad5, but does not mention the genes that are internalized in the cell cytoplasm and eventually in the nucleus of these eucaryotic cells. Similarly, U.S. Pat. No. 5,521,291 relates to conjugated adenovirus bound through an antibody to a substance with affinity for nucleic acids. In this way recombinant genes are transported to the interior of eucaryotic cells. These conjugated complexes and nucleic acids are internalized in the cell, but the genes that can be sent are not specifically mentioned. In said patent, contrary to what is described in the instant invention, the use of such adenovirus to treat liver fibrosis or cirrhosis or any another type of fibrosis is not mentioned.
U.S. Pat. No. 5,585,362 relates to an improved adenoviral vector and methods to obtain and use such vectors. Although the use of adenoviral vectors is not mentioned in said patent, the adenoviral vectors described in the present invention were used as vectors for sending therapeutic genes.
U.S. Pat. No. 5,756,086 claims an adenovirus, which is represented by a protein called “fiber”. The adenovirus also includes a ligand, that is specific for a receptor located on a specific cell type. This adenovirus can have at least a portion of this protein called “fiber” and it can be removed and replaced with a ligand, which is specific for a receptor on specific cells, such as hepatocytes. These adenoviruses can include a gene that codes for a therapeutic agent. Based on the previous statement, the outstanding technical difference of the instant invention, compared to the state of the art, is the specificity of the therapeutic agent as wild and/or modified huPA and the TGF-beta type II truncated receptor for the treatment of various fibrosis.
U.S. Pat. No. 5,895,759 claims a tissue-specific vector (liver) for gene therapy that can be used to send genes to a damaged liver. These vectors are chemically or enzyme coupled to a promoter and can also be coupled to an antibody packaged in a polypeptidic envelope. Besides, the vector or the virus to be assayed is the hepatitis B virus. Thus the sending of genes to damaged livers described in this patent makes use of a system completely different from the one of this invention, and there is no relation with the process of fibrosis or cirrhosis to be treated. U.S. Pat. No. 5, 559,099 describes an adenoviral recombinant vector that contains a chimeric protein from the adenovirus called pentona, which includes a non-pentona sequence and a therapeutic gene to develop a gene therapy method involving the use of such adenovirus, transference adenoviral vectors for the recombination of such adenoviral vectors containing a therapeutic gene. Moreover, U.S. Pat. No. 5,885,808 claims also the use of adenovirus with bonding molecules of adenovirus to different cells, the molecules of which have been modified, as in U.S. Pat. Nos. 5,846,782 and 5,712,136, in which adenoviral vectors are employed, which have been modified to contain different peptidic domains.
Finally, U.S. Pat. No. 5,670,488 relates to vectors for gene therapy, which are especially useful for cystic fibrosis and also mentions the development of methods for the use of these vectors. The possible relation of the instant invention to the mentioned state of the art refers to the use of adenoviral vectors, that can be modified, as well as the use of inducible promoters driving the expression of genes to be inserted in these adenoviral vectors. However, the technical characteristics of the present invention are focused on the specific use of therapeutic genes to treat different types of fibrosis such as liver, kidney, lung, pancreas, heart fibrosis, keloids, as well as hypertrophic scars.
The importance of the present invention, contrary to the state of the art described in the above-mentioned documents, is based on the technical characteristics of the invention itself, as well as on the additional advantages derived from the same, which are described with more details below.